How To Install Underground Dog Fence Under Driveway, Pathway, or Sidewalk

Looking to finish installation of your underground dog fence or invisible fence and wondering how to get it across the driveway? In this article we’ll show you how to install an underground fence under your driveway or path.

Plus we’ll also cover a few other options like laying it across the driveway, using an expansion joint, cutting a new slot, and tunneling under your driveway.

Note: If you click some of the links in this article we may earn a small commission at no additional cost to you.

Will You Have To Dig Up My Drive To Install The Invisible Fence?

No, you won’t have to dig up your driveway in order to install the underground dog fence wire. You have lots of options. The most common is to use an existing joint at either end of the driveway or one of the expansion joints through the center of the driveway.

You can also use a circular saw with a masonry blade to cut a new slot. If you hired a professional this is what they would do. This gives you the greatest control on where to put the dog fence wire so it matches the layout you’ve chosen.

If you have a super long driveway and it’d be inconvenient to use an expansion joint and you don’t want to cut a new slot then you can also tunnel under the driveway using PVC pipe.

Lastly some people do just lay the dog fence wire right on top of the driveway surface. They drive over it daily and simply replace it when it wears out. This by far is the easiest method though a bit unsightly and could be a tripping hazard.

What Are All My Options?

Here are all your options for crossing a driveway with an in-ground dog fence wire. We’ll cover how to do each one in later sections below. Watch the videos that go along with each section.

  • Easy, 5-30 Minutes – Run the Dog Fence Wire Over Your Driveway
  • Easy, 5-30 Minutes – Run PVC conduit through an existing pipe (e.g. drainage pipe) under the driveway then run wire through PVC conduit
  • Medium Difficulty, 30 – 60 Minutes – Use an Expansion Joint
  • Medium to Hard, 1-2 Hours (including time to buy or rent equipment) – Cut a Slot with a Circular Saw
  • Hard, 2 – 4 hours – Tunnel Under the Driveway

How Do I Run The Wire Over My Driveway?

This is the most basic and easiest method. Simply run the wire over your driveway. It’s a trip hazard but it’s fast and easy! Then when the boundary wire wears out you can replace it as needed.

This method lasts the least amount of time. Expect to get 1-2 years from this method. You can extend that time a bit by running it through a black garden hose to protect it from traffic.

Make change outs easier by installing underground waterproof splices at both ends of the driveway.

Waterproof Invisible Fence Repair Splice Kit, Pack of 4.

Using An Expansion Joint

The next method involves using an existing expansion seam. You can also use the beginning where your driveway connects to the front sidewalk. The last place you can use is the end of the driveway where it connects to the garage.

Here’s what you need to do to use an expansion joint:

  1. Use a flat blade (e.g. garden hand trowel) to widen the joint or cut out the existing caulking. Widening only works with soft asphalt. Concrete driveway joints can only be expanded through pulling out the existing caulk or using a masonry saw as described in the next section. This method works great for gravel driveways and dirt driveways.
  2. Lay the wire through the expanded groove
  3. Caulk over the boundary wire or simply wait and allow dirt and debris to cover it up.
  4. Optional end extra protection – Protect the ends with waterproof splice kits and a small length of PVC pipe. The PVC pipe must be installed slightly under the driveway. It’s job is to protect the wire when you use edging equipment on the lawn next to the driveway. The splice kits make it easy to change out this wire later if it ever gets damaged from driveway traffic.
  5. Watch the video below for a demonstration
Edward Tools Bend-Proof Garden Trowel - Heavy Duty Polished Stainless Steel - Rust Resistant Oversized Garden Hand Shovel for Quicker Work - Digs Through Rocky/Heavy soils - Comfort Grip (1)
Use a Garden Trowel to widen the existing joint or cut out the caulk.
Sikaflex Self-Leveling Sealant, 10.1 fl. oz Cartridge, Gray
Caulk over the boundary wire after you lay it down to protect it.

Cutting a New Slot With a Circular Saw With a Masonry Blade

What if you don’t have an expansion joint where you want to lay the line? Then you make your own by cutting a new joint with a masonry blade.

Here’s how:

  1. Use a chalk line to draw the new line you want to cut
  2. Rent or buy a circular saw with a masonry blade
  3. Cut the line. Don’t forget to use gloves and eye protection! It’s best not to have people or dogs nearby that could accidentally get hit by flying debris.
  4. Lay in the underground dog fence wire.
  5. Use concrete caulk over it.
  6. Optional end protection – Protect the ends with waterproof splice kits and a small length of PVC pipe. The PVC pipe must be installed slightly under the driveway. It’s job is to protect the wire when you use edging equipment on the lawn next to the driveway. The splice kits make it easy to change out this wire later if it ever gets damaged from driveway traffic.
  7. Watch the video below for a demonstration
DEWALT Diamond Blade for Block and Brick, Dry/Wet Cutting, Continuous Rim, 7-Inch (DW4712)
Use a diamond blade or masonry blade to cut through your cement or asphalt driveway
SKILSAW SPT79-00 15-Amp MEDUSAW Worm Drive Saw for Concrete, 7"
Use a Saw Designed to Cut Concrete

How to Tunnel Under the Driveway

The last method is to tunnel under the driveway using PVC or metal piping. Metal piping will drill better but may interfere with the signal. PVC piping is recommended as it won’t interfere with the signal.

You can also drill the initial line with metal pipe a 1/2 foot at a time and remove soil as you go then go back in with PVC pipe. This is risky though depending on your soil type. If the soil collapses above the tunnel you could cause a crack or break in the driveway when driving over it.

This is by far the hardest and most labor intensive method. A professional installer will not do this as it would cost you too much.

If you have no other option or you simply don’t want to change the look of your driveway from the cutting method then this method is for you.

This method is often used with stone driveways.

Option 1 – The Water Drilling Method

This method is nice as it’s far easier than the hammer method.

Use this when you have a solid driveway that doesn’t crack easily (e.g. thick concrete or cobblestone or pavers). The water drilling method will soften up the soil underneath and the weight of vehicle traffic could cause cracking. If that’s a worry use the more laborious hammer method shown below.

Here’s what to do to water drill under a driveway or sidewalk:

  1. Use a chalk line to mark where you want the tunnel to go.
  2. Dig a small hole on both sides of the driveway
  3. Get enough PVC pipe to cross the driveway.
  4. Get a walkway tunnel kit and attach it to the end of the PVC pipe. See picture below. It uses pressurized water to water drill through the soil. The entire package comes with a water nozzle tip and a hose end.
  5. Attach hose to other end of PVC pipe using the walkway tunnel kit.
  6. Turn on water and begin water drilling under the driveway or walkway. You’ll be pushing at roughly a 15 – 30 degree angle from one side. Try to get down to a 0 degree angle if possible. You can do that by digging out a longer side trench.
  7. Repeat for the entire length under the driveway.
  8. Note you can skip the water method and use a sharpened piece of pipe end with a hammer. Then just hammer it through and pull out soil every 6 inches or so. This works best with soils that are less rocky or if you fear the soil will collapse the driveway using the water method.
  9. Don’t go deeper than a 3 inch trench or you may lose the signal.
  10. Optional end protection – Protect the ends with waterproof splice kits and a small length of PVC pipe. The PVC pipe must be installed slightly under the driveway. It’s job is to protect the wire when you use edging equipment on the lawn next to the driveway. The splice kits make it easy to change out this wire later if it ever gets damaged from driveway traffic.
  11. Watch the video below for a demonstration
2 Pack - Orbit Sprinkler System Walk Way Tunnel Boring Kit
Walkway Tunnel Kit – Uses pressurized water at the tip to drill through soil

The Hammer Drilling Method

This method is more classic and old school. Essentially you use a metal pipe and a hammer to hammer through the soil. This was used to drill shallow wells and still is used for the same.

The technique for well drilling has been applied to getting under a driveway.